When there are heterogeneous communication systems which share the same band, a Frequency Hopping spread spectrum (FHSS) system can avoid interference using a frequency hopping (hereinafter referred to as “FH”) technique at high speed. For example, a Bluetooth system which is a kind of FHSS system reduces the influence of heterogeneous types of interference using a pseudo-random FH method at a speed of 1600 times per second. This FH technique is disadvantageous in that it is very vulnerable to co-channel interference because an FH channel is determined according to the clock and the address value of a transmission unit without regard to radio interference.
An adaptive FH (hereinafter referred to as “AFH”) technique proposed in IEEE 802.15 TG2 classifies channels, in which co-channel interference is present, using a channel classification procedure, and determines FH bands based on the results of the classification, thus avoiding co-channel interference. However, such an AFH technique is disadvantageous in that since FH bands are classified on the basis of the channels of an FHSS system, the time required to classify bands increases, thus coping with co-channel interference slowly.
In addition, in the case where FD interference signals causing interference in narrow band channels for a short period of time are present, if channels in which interference occurs are excluded from frequency hopping channels as in the case of the AFH technique, the number of available frequency hopping channels is reduced instead, so that the probability of colliding with another Frequency Dynamic (FD) interference increases, thus deteriorating system performance.
Further, a power control technique has been considered in various types of wireless communication systems such as Bluetooth systems. Such a power control technique is advantageous in that transmission power is adjusted based on the results of the classification of channels, and then both co-channel interference and channel noise can be rapidly mitigated, but it is disadvantageous in that when a larger number of interference sources are present in a relevant wireless communication system, power consumption increases rapidly.